Retaining assembly for tapered roller bearings

ABSTRACT

A retaining assembly providing a simplified means and procedure for mounting tapered roller bearings on a shaft in a manner as also insures accurate bearing setting. Said assembly includes a plain metal washer which is located by and held tight and square against the conventional shoulder provided on the shaft which is to receive such a bearing just outwardly of its journal portion by the axial biasing action which a beveled retaining ring sprung into a circumferential groove provided therefor in the shaft just outwardly of said outer shoulder exerts thereon in tending to contract to its unstressed diameter (cf. U.S. Pat. No. 2,509,081, dated May 23, 1950).

United States Patent Wurzel [451 Aug. 1, 1972 [54] RETAINING ASSEMBLYFOR FOREIGN PATENTS OR APPLICATIONS TAPERED ROLLER BEARINGS 192,19610/1957 Austria...., ..287/207 [72] Inventor: Hugo Wurzel, Rego Park,NY.

Primary Examiner-Houston S. Bell, Jr. [73] Ass1gnee. Waldes Rochinoor,lnc., Long Island Atmmey l Harold Kflcoyne City, NY. [22] Filed: Jan.22, 1970 [57] ABSTRACT I 211 4,397 A retaining assembly providing asimplified means and procedure for mounting tapered roller bearings on ashaft in a manner as also insures accurate bearing (3| /DlG. 7, 30 /23setting. Said assembly includes a plain metal washer [51] Int. Cl...Fl6c 33/00 which is located by and held tight and square against [58]Field of Search ..308/2l8, 197, 207, 236; the conventional shoulderprovided on the shaft which 287/DIG. 7; 85/8.8, 50 is to receive such abearing just outwardly of its journal portion by the axial biasingaction which a beveled 5 References Cited retaining ring sprung into acircumferential groove provided therefor in the shaft just outwardly ofsaid UNITED STATES PATENTS outer shoulder exerts thereon in tending tocontract to 1,418,379 6/1922 Karle ..287/DIG. 7 323 523 3; ggg 25099812,509,081 5/1950 Bluth et al ..287/DIG. 7 2,595,787 5/1952 Heimann..287/DIG. 7 7 Claims, 10 Drawing Figures PATENTED M1 1 I97? sum 2 OF 2lNVliNTOR fufid 444/2241,

ATTORNEY RETAINING ASSEMBLY FOR TAPERED ROLLER BEARINGS BACKGROUND OFTHE INVENTION It is well known to those skilled in the particular artthat to get maximum bearing life from bearings, and

particularly tapered roller bearings comprising axiallyspaced sets ofoppositely tapered roller bearings in which correspondinglyaxially-spaced stepped diameter shaft portions are joumaled, as are usedin many and varied shaft applications, it is necessary to have accuratebearing setting. That is to say, tapered roller bearings set withoutproper running clearance, either too tight or too loose, between theouter-end face thereof and such bearing retention means as is employed,will not give the life that was designed into them. Conversely, properbearing setting insures equal load distribution over all the workbearing surfaces and hence makes for longer bearing life.

In the past, the setting of tapered roller bearings on shafts wasconsidered to be a job to be undertaken only by experienced personnelemploying special measuring devices designed to insure accurate setting,and thus accurate initial setting and subsequent resettings of suchbearings on the journal portion of a shaft as might be required in thefield was very difficult if not altogether impossible of attainment.

More recently, however, it became more or less standard practice in theart to effect the mounting of tapered roller bearings on a shaft and atthe same time to achieve accurate setting thereof by providing the shaftwith a reduceddiameter, outer-end length portion which is separated fromthe journal portion thereof on which the bearing is directly mounted bya right-angular shoulder disposed at a distance outwardly from an innerreference shoulder usually also provided on the shaft to define theinnermost line of the bearing sets, which is greater than the overallwidth of the bearing by the small amount which exactly equals therunning clearance to be provided the bearing according to the particulardesign requirements of the installation. A thread cut in the peripheralsurface of said reduced-diameter outer-end portion of the shaft for thelength thereof provides for the threading thereon of a self-locking nutwhich is run squarely up against the aforesaid outer shoulder, thus. toprovide not only a bearing retention means but also a shoulder solocated as to provide the proper running clearance between the outer-endface of the bearing and said retention means (screw-on nut).

SUMMARY OF THE INVENTION The retaining-ring assembly and the procedurefor mounting tapered roller bearings on shafts in a manner as insuresaccurate bearing setting according to the present invention alsorequires a reduced-diameter outer-end portion on the shaft, theprovision of which forms a shaft shoulder at the same developed distancefrom the bearing reference shoulder as establishes the proper runningclearance between the bearing reten tion means and the outer end of thebearing, as just explained in connection with the prior method using ascrew-on lock'nut form of bearing retention means. However, the hereininvention provides for the retention and accurate setting of the bearingby a plain metal washer which in installation is simply slipped over thereduced-diameter end portion of the shaft and shifted axially therealongto a position in which it abuts square against said outer-shaftshoulder, in which position it is positively and forcefully retained bya beveled retaining ring sprung into a circumferential groove providedtherefor in the periphery of the reduced-diameter shaft-end portion justoutwardly of the so-positioned washer, and which, in tending to contractto its unstressed state, exerts a substantial force in axial directionagainst the outer face of said washer as positively holds it againstsaid shoulder.

Advantages of the aforesaid beveled retaining ringwasher means forretaining tapered roller bearings as herein proposed on their shaftsover the present locknut form of bearing retaining means are as follows:A much shorter length of reduced-diameter shaft end and no screwthreading of said shaft end is required; the replacement of the lock-nutretention means by a simple inexpensive stamped washer, the tolerancesin the thickness of which can be held to commercial sheetmetaltolerances since the beveled retaining ring component of the retentionmeans has only to take up these tolerances and the groove-locationtolerances which a properly designed beveled retaining ring can easilydo; and the ability of the retaining ring and washer form of bearingretention means of the invention to perform as intended time-after-timeeven under field conditions.

For detailed explanation of the major structural features of theinvention, reference is had to the accompanying illustrative drawingswhich are to be read in' light of the following written description, inwhich:

FIG. 1 is a side elevation, partially in section, illustrative of atapered roller bearing mounted on a shaft according to the prior artmeans and method therefor;

FIG. 2 is a view similar to FIG. I but illustrating the simplifiedbeveled retaining ring and washer means serving to mount a taperedroller bearing in the shaft according to the present invention;

FIG. 3 is a front-end elevation of the mounted tapered roller bearingassembly illustrated in FIG. 2;

FIG. 4 is an enlarged fragmentary view, partly in section, taken alongline 4-4 of FIG. 3;

FIG. 5 is a front elevation looking on to the beveled retaining ringcomponent of the bearing retention means as employed in FIGS. 2-4, andFIG. 6 is an enlarged section taken on line 5-5 of FIG. 5;

FIGS. 7A and 7B are front elevation and vertical sections, respectively,of the washer component of the bearing retention means employed in FIGS.24;

FIG. 8 is a part-sectional view similar to FIG. 4 but employing anoptional configuration of the washer and shaft end useful in preventingrelative rotation between washer and shaft in applications where loadingconditions are on the high side; and

FIG. 9 is a front elevation of the modified washer employed in thebearing mounting assembly of FIG. 8.

For a proper understanding of the simplified means and the proceduremade possible thereby for mounting tapered roller bearings as used innumerous and varied shaft applications as are provided by the presentinvention, such will be described against the present widely used meansillustrated in FIG. 1. More particularly, reference numeral 10 (FIG. 1)designates the bearingjoumaled end of a shaft which extends into ahollow housing 12, which includes axially spaced, steppeddiameterjournal portions l4, l6 interconnected by a tapered portion 18. Thestepped-diameter journal portions l4, 16 are journaled for relativerotation in the inner races of correspondingly spaced, tapered rollersets generally designated 20, 22, the outer races of which have pressfit in the bore-wall surface of the housing 12.

Said shaft 10 is provided at its relatively outer end with areduced-diameter end portion 24, the reduction in diameter of whichresults in the formation of an outer right-angular shoulder 26 which, aspreviously explained, is so located along the length of the shaft thatwhen bearing retention means operating as a shoulder is positionedsquare against same, proper running clearance for the tapered rollerbearing assembly is also insured. Also, as earlier stated, the bearingretention means employed in the prior-art bearing mounting means shownin FIG. 1 comprises a lock nut 28 which is threaded on to the reduceddiameter end of the shaft (for which purpose said shaft end is providedwith screw threads throughout substantially its full length) to aposition in which it is disposed tight and square against said shoulder26.

From the description up to this point, it will be seen that the presentmethod of mounting a tapered roller bearing on the outer-end journalportion of a shaft, axle and the like requires the provision of anexteriorly threaded, reduced-end portion of substantial axial length attheextreme outer end of said shaft, plus the provision of bearingretention means in the form of a lock nut which must be carefullythreaded thereon to prevent cross-threading of the threads of each andthereafter run up square and wrenched tight against the outer shoulder26 of the shaft. As distinguished therefrom, the bearing retention meansof the present invention substitutes for the threaded-on lock nut of theprior bearing mounting means as just described a simple sheet-metalwasher capable of being readily slipped over the reduceddiameter end ofthe shaft 240 and thereupon of being merely pushed axially therealonginto engagement with a shaft shoulder corresponding in all respects tothe aforementioned shoulder 26, against which it is thereafterpositively held by the biasing action exerted thereon in axial inwarddirection by a beveled retaining ring of the type disclosed in US. Pat.No. 2,509,081, dated May 23, 1950, which is sprung into a groove cut orotherwise machined in the reduced-diameter end of the shaft justoutwardly of the so-positioned washer.

More particularly, and as depicted in FIGS. 2-4 inclusive, illustrativeof a bearing retained on a shaft in accurately set position by thesimplified retention means of the herein invention, the details of whichare illustrated in FIGS. 5-73 inclusive, such retention means comprisesa plain sheet-metal washer 30 (FIG. 7A), whose central opening asdefined by its inner circular edge 32a has diameter slightly greaterthan that of the diameter of the reduced-diameter end of the shaft,whereby it can be readily slipped over said end and shifted axiallytherealong to a position in which it abuts the aforesaid shaft shoulder26, and whose outer diameter is substantially greater than that of thediameter of thejournal portion 16 of said shaft, whereby its outer rimor edge portion 32b projects radially beyond said journal portion, thusto form an artificial shoulder thereon.

' the shaft at a location along the latter as insures tight interfaceengagement being established between the relatively inner radial face ofsaid retaining ring 34 and the relatively outer radial face of thewasher 30.

As the structure and manner of functioning of a beveled retaining ring(as herein designated 34) when sprung into a shaft groove (as hereindesignated 36) are well known, such being the subject matter of nowexpired US. Pat. No. 2,509,081, dated May 23, 1950, no detaileddescription thereof is believed necessary. Suffice it to say, however,that when said ring 34 is sprung into its groove, it is spread andthereby stressed, following which it tends to close circumferentially,i.e. to contract to its unstressed state. Being of so-called beveledconstruction, said ring 34 is provided on its face which is remote ordistant from the washer 30 and along its inner edge with an inclinedsurface 34a and the side wall 360 of the groove 36 against which saidring surface 34a engages is complementally inclined. Thus, anycircumferential closing or contraction of the ring causes it to move inaxial direction against the washer 30 with a force which, with properdesign of the ring, can be of the magnitude to hold said washer tightagainst said shaft shoulder 26.

From the above, it will be appreciated that the retaining ring andwasher-type bearing retention means as aforesaid provides both a simpleand practical means of mounting tapered roller bearings on shafts, ascompared to the screw-on lock nut type of bearing retention means of theprior art. Further, and as noted in the foregoing, the retaining ringand washer-type bearing retention means is also less costly than theprior screwon lock nut means, since its employment requires a muchshorter length of reduced-diameter shaft end than does said lock nutmeans and similarly requires no cutting of threads in thereduced-diameter end of the shaft. Yet another advantage of the bearingretention means of the invention is that the washer which is employed inplace of the threaded screw-on lock nut as previously used may bereadily and inexpensively fabricated by stamping same in quantity fromsheetmetal stock, and in this connection it is worthy of mention thattolerances in the thickness of said sheet-metal stock can be held tocommercial sheet-metal tolerances since the beveled retaining ring whichis used therewith according to the invention is entirely capable oftaking up the tolerances in washer thicknesses as well as in groovelocation.

Yet another practical feature of the retaining ring and washer-typebearing retention means of the invention is that beveled retaining ringsas used therein may be readily assembled and thereafter re-assembled intheir grooves, being for this purpose provided with apertured ears withwhich the tips or points of the pliertype assembly and disassembly toolsmay be readily coupled. Accordingly, bearing retention means employingsuch a beveled retaining ring may be disassembled and reassembled timeafter time even under field conditions, with assurance not only ofadequate hearing retention but also of accurate bearing setting.

To provide for the condition of heavy loading which might causeundesirable relative rotation of the washer 30 and possibly also of theretaining ring 34 with respect to the shaft or shaft end, the use of thesomewhat modified configuration of shaft and washer inner edge of FIGS.8 and 9 is suggested. According thereto, the reduced-diameter outer-endportion 24a of the shaft 10 is provided with a flat 40 and the washer 38is provided along its inner edge with a matching flat designated 40awhich extends as a chord across its otherwise circular inner edge. Bythe provision of these matching flats, said washer 38 is .in effectkeyed to the shaft end and is thus restrained against any relativerotation with respect thereto. Otherwise the FIG. 8 form of bearingmounting and retention means is structurally and functionally identicalwith that previously described in connection with FIGS. 24 inclusive.

As many changes could be made in carrying out the above constructionswithout departing from the scope of the invention, it is intended-thatall matter contained in the above description or shown in theaccompanying drawings shall be interpreted as illustrative and not in alimiting sense.

I claim:

1. Means mounting and accurately setting tapered roller bearings forwheels and the like on a shaft provided with a journal portionterminating in a conventionally-located outer shoulder and areduced-diameter outer-end portion which extends axially beyond saidshoulder, comprising: washer means assembled on said reduced-diameterouter-end portion of the shaft and having effective outer diametergreater than that of the immediately adjacent journal portion thereof,and readily removable and replaceable retaining-ring means assembled onsaid reduced-diameter end of the shaft axially-outwardly of said washermeans and exerting continuous axial force in inward direction on saidwasher means of a magnitude maintaining said washer means in tightabutting engagement against said shoulder, the construction andarrangement being such that said outer-end portion of the shaft isunconventionally non-threaded and of relatively short length and furtherthat proper running clearance is assured.

2. Means according to claim 1, wherein said washer means comprises astamping of annular shape fashioned from commercial sheet metal whosecentral opening has diameter slightly greater than that of the shaftouter-end portion whereby it may be assembled and positioned thereon bybeing slipped over said outer-end portion and shifted axially therealongto an initial shoulder-abutting position as aforesaid.

3. Means according to claim 1, wherein said retaining-ring meanscomprises a beveled spring-retaining ring assembled and being instressed condition in a circumferential groove provided therefor in theperipheral surface of said outer-end shaft portion outwardly of saidshaft shoulder, said retaining ring in tending to return to itsunstressed condition exerting inward axial force on the outer face ofsaid washer means of magnitude as holds said washer means in forcefulabutting engagement against said shoulder as aforesaid.

4. Means according to claim 2, and wherein said retaining-ring meanscomprises a beveled springretaining ring assembled and being in stressedcondita gasaiaa sauslaraaaaza a "55%;: outwardly of said shaft shoulder,said retaining ring in tending to return to its unstressed conditionexerting inward axial force on the outer face of said washer ofmagnitude as holds said washer in forceful abutting engagement againstsaid shoulder as aforesaid.

5. Means according to claim 4, and wherein said circumferential grooveis defined in part by side walls and one of said side walls hasinclination complemental to that of the bevel of said retaining ring,said one side wall cooperating with said bevel in rendering saidretaining ring operative to exert inward axial force on the outer faceof the washer as aforesaid.

6. Means according to claim 1, wherein said washer means andreduced-diameter outer end of the shaft are provided with cooperatingmeans preventing relative rotation of the washer means with respect tosaid shaft outer-end portion on which said washer means is mounted.

7. Means according to claim 6, and wherein said last means comprises aflat on the surface of the shaft outer end and a mating flat on theinner edge of said washer means.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Petentflkr ,95Datmi August 1, 1972 Inventor(s) Hugo rzel It is certified that errorappears in the above-identified patent and that said Letters Patent arehereby corrected as shown below:

Column 2,-Iine 48, "5-5" should read 6 6 Column 4, line 22, "distant"should read distal Column 5, line 6, "edge" should read edges On thecover sheet the assignee should read Waldes Kohihoor, Inc;

Signed and sealed this 5th day of November l974.

. (SEAL) Attest:

McCOY M. GIBSON JR. 0. MARSHALL DANN Attesting Qfficer Commissioner ofPatents -'oR-iPo-1oso(1o-s9) I A USCOMM-DC BO370-P69 11.54 GOVERNMENYPRINTING OFFICE: 869- 93 o

1. Means mounting and accurately ''''setting'''' tapered roller bearingsfor wheels and the like on a shaft provided with a journal portionterminating in a conventionally-located outer shoulder and areduced-diameter outer-end portion which extends axially beyond saidshoulder, comprising: washer means assembled on said reduced-diameterouter-end portion of the shaft and having effective outer diametergreater than that of the immediately adjacent journal portion thereof,and readily removable and replaceable retaining-ring means assembled onsaid reduced-diameter end of the shaft axially-outwardly of said washermeans and exerting continuous axial force in inward direction on saidwasher means of a magnitude maintaining said washer means in tightabutting engagement against said shoulder, the construction andarrangement being such that said outer-end portion of the shaft isunconventionally non-threaded and of relatively short length and furtherthat proper running clearance is assured.
 2. Means according to claim 1,wherein said washer means comprises a stamping of annular shapefashioned from commercial sheet metal whose central opening has diameterslightly greater than that of the shaft outer-end portion whereby it maybe assembled and positioned thereon by being slipped over said outer-endportion and shifted axially therealong to an initial shoulder-abuttingposition as aforesaid.
 3. Means according to claim 1, wherein saidretaining-ring means comprises a beveled spring-retaining ring assembledand being in stressed condition in a circumferential groove providedtherefor in the peripheral surface of said outer-end shaft portionoutwardly of said shaft shoulder, said retaining ring in tending toreturn to its unstressed condition exerting inward axial force on theouter face of said washer means of magnitude as holds said washer meansin forceful abutting engagement against said shoulder as aforesaid. 4.Means according to claim 2, and wherein said retaining-ring meanscomprises a ''''beveled'''' spring-retaining ring assembled and being instressed condition in a circumferential groove provided therefor in theperipheral surface of said outer-end shaft portion outwardly of saidshaft shoulder, said retaining ring in tending to return to itsunstressed condition exerting inward axial force on the outer face ofsaid washer of magnitude as holds said washer in forceful abuttingengagement against said shoulder as aforesaid.
 5. Means according toclaim 4, and wherein said circumferential groove is defined in part byside walls and one of said side walls has inclination complemental tothat of the bevel of said retaining ring, said one side wall cooperatingwith said bevel in rendering said retaining ring operative to exertinward axial force on the outer face of the washer as aforesaid. 6.Means according to claim 1, wherein said washer means andreduced-diameter outer end of the shaft are provided with cooperatingmeans preventing relative rotation of the washer means with respect tosaid shaft outer-end portion on which said washer means is mounted. 7.Means according to claim 6, and wherein said last means comprises a''''flat'''' on the surface of the shaft outer end and a mating''''flat'''' on the inner edge of said washer means.